Marsh and wetland rehabilitation system and associated methods

ABSTRACT

A method for constructing or rehabilitating a marsh or wetland comprises the step of inserting propagatable material into liquid or slurry emerging from a high-pressure spray nozzle to form a mixture. The liquid/ or slurry/propagatable material mixture is then sprayed over a marsh or wetland area desired to be constructed or rehabilitated.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to systems and methods for constructingand rehabilitating marshes and wetlands, and, more particularly, to suchsystems and methods that are ecologically beneficial.

2. Description of Related Art

The present inventor has previously disclosed methods for building orrestoring marshes and beaches, and also for dredging waterways in anenvironmentally friendly and cost-effective manner. These methods, whichare disclosed, inter alia, in U.S. Pat. Nos. 3,971,148; 4,240,243;4,434,943; 4,517,754; 4,521,305; 4,575,960; 4,628,623; 4,759,664;4,896,445; 5,167,469; and 5,211,511, which are incorporated by referencehereinto, utilize a high-pressure nozzle to spray a thin layer of slurrymaterial over a large area. In the '148 patent, a dredge cutter head isdescribed that is self-cleaning; in the '243 patent, satelliteharvesters are used to harvest underwater aquatic growth; in the '943patent, a pump intake cutter head is disclosed for pumping an aquaticgrowth slurry from a waterway or body of water; in the '754 and '960patents, a cutterhead attachment for a dredge is described; in the '305patent, a rotating self-cleaning screen is provided; in the '623 patentis described a turbidity control system for a dredge cutterhead; in the'664 patent, the slurry is formed of a solid material and water at afirst location and pumped to a remote location for increasing theelevation of an area at the remote location; in the '445 patent, awaterway is dredged, and the dredged material is used to form a slurrythat is then distributed over the adjoining area in a layer sufficientlythin to avoid negative impact on the environment; in the '469 and '511patents, a slurry distribution system is disclosed.

Natural habitat disappearance is a persistent problem, and can be causedby a variety of damaging factors, including, but not limited to,human-caused factors and pollution. Until now, marsh and wetlandrestoration has been an expensive and labor-intensive process, sincere-planting heretofore has been performed manually.

SUMMARY OF THE INVENTION

An aspect of the present invention is directed to the construction andrehabilitation of marshes and wetlands in particular, and in thedispersion of seed and/or vegetative material in general. Suchvegetative material may include, but is not intended to be limited to,fragments or plants that will propagate on their own.

In one embodiment is provided a method for rehabilitating a marsh orwetland. The method comprises the step of inserting seed and/orvegetative material into liquid or slurry emerging from a high-pressurespray nozzle to form a mixture. The mixture is then sprayed in a thinlayer over a marsh or wetland area desired to be re-seeded orre-vegetated.

A system of the present invention in one aspect is for rehabilitating amarsh or wetland. The system comprises a container for holding seeds anda high-pressure spray nozzle. A hose is in fluid contact with a sourceof liquid at a first end and the spray nozzle at a second, opposed end.

A pump is provided for pumping liquid from the liquid source into thehose. Also provided is a conveyance tube that leads from the seedcontainer to an aperture in the hose. The aperture is positioneddownstream of the pump, so that, when the nozzle is in use, a vacuum iscreated at the aperture for drawing seed into a liquid stream beingejected by the spray nozzle to form a liquid-seed mixture. Means arealso provided for directing the spray of liquid-seed mixture over adesired area remote from the liquid source.

In an alternate embodiment a system is provided that comprises acontainer for holding seeds and a mixing tank having means for agitatingcontents thereof. A means for transporting seeds from the container andliquid into the mixing tank is also provided, along with a high-pressurespray nozzle.

A hose is in fluid contact with the mixing tank at a first end and thespray nozzle at a second, opposed end. A pump is provided for pumpingmixed seed and liquid from the mixing tank into the hose. Means areprovided for directing the spray of liquid-seed mixture over a desiredarea remote from the liquid source.

The present invention provides considerable savings in cost and time toconstruct or rehabilitate a marsh or wetland.

The features that characterize the invention, both as to organizationand method of operation, together with further objects and advantagesthereof, will be better understood from the following description usedin conjunction with the accompanying drawing. It is to be expresslyunderstood that the drawing is for the purpose of illustration anddescription and is not intended as a definition of the limits of theinvention. These and other objects attained, and advantages offered, bythe present invention will become more fully apparent as the descriptionthat now follows is read in conjunction with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a system for distributing a liquid-seedmixture over an area to be rehabilitated.

FIG. 2 is a top plan view of a second embodiment of a system fordistributing a liquid-seed mixture over an area to be rehabilitated.

FIG. 3 is a side view of the system of FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A description of the preferred embodiments of the present invention willnow be presented with reference to FIGS. 1-3.

A first embodiment of a system 10 (FIG. 1) of the present invention,believed at the time of filing to represent a preferred embodiment, inone aspect is for constructing or rehabilitating a marsh or wetland 11.The system 10 comprises a container for holding seeds and/or otherpropagatable vegetative material 12. The vegetative material will in thefollowing be referred to as “seed,” although other propagatable materialis also intended to be subsumed under this term. In addition to theseeds and/or vegetative material, other additives may be included, suchas, but not intended to be limited to, fertilizer, a pH-adjustingcomposition, seed stabilization and placement enhancers, and slurrystabilization enhancers.

In a preferred embodiment the container comprises an agitator tank 13into which the seeds 12 are directed and mixed with water or with aslurry of dredged material and water. A hose 14 is in fluid contact witha source of liquid, such as a body of water 15, at a first end 16. Ahigh-pressure spray nozzle 17 is attached to the hose 14 at a second end18 opposed to the first end 16.

In the first embodiment 10, a pump 19 is positioned upstream of theagitator tank 13 for pumping liquid or slurry (which will be referred tohereinafter as “liquid”) from the liquid source 15 into the hose 14. Aconveyance tube 20 leads from the agitator tank 13 to an aperture 21 inthe hose 14. The aperture 21 is positioned downstream of the pump 19, sothat, when the nozzle 17 is in use, a vacuum is created at the aperture21 for drawing seed 12 into a liquid stream 22 being ejected by thespray nozzle 17 that comprises a mixture of the contents of the agitatortank 13 and liquid from the source 15. The angle 23 at which the tube 20meets the hose 14 will determine the rate at which the seed 12 is drawninto the stream 22.

Means are also provided for directing the spray 22 of liquid-seedmixture over a desired area 11 remote from the liquid source 15. Such adirecting means may comprise, for example, devices such as are disclosedin the previously cited '664 or '445 patents, although these are notintended as limitations.

A second embodiment of the reseeding system 30 (FIGS. 2 and 3) includesa container 31 for holding seeds 32 and a mixing tank 33 having meansfor agitating contents thereof. A pump 34 is used for transportingliquid 35 from, for example, a body of water 36 into the mixing tank 33.

A hose 37 is in fluid contact with the mixing tank 33 at a first end.The hose 37 extends to the suction side of the pump 34, with the suctiondrawing the mixture 40 into the stream. A high-pressure spray nozzle 38is in fluid contact with the pressure side of the slurry pump 34 at asecond, opposed end 39. The pump 34 also serves to pump, by suction, theseed and liquid mixture 40 from the mixing tank 33 into the suction hose37.

As described above, means are provided for directing the spray ofliquid-seed mixture 40 over a desired area remote from the liquid source36.

In another embodiment, a separate pump 23 could be provided for pumpingseed from the container into the slurry on the pressure side of theslurry pump, pumping at a greater pressure than that of the pressurizedslurry.

These systems 10,30 can be a component of a unitary dredging unit havinga cutting head 41 at a front end 42 and means for channeling the dredgedmaterial in a slurry to the nozzle 38, as described in the presentinventor's previously issued patents. Thus in a single step, bothdredging, construction, and rehabilitation are effected, positivelyaffecting the environment.

In the foregoing description, certain terms have been used for brevity,clarity, and understanding, but no unnecessary limitations are to beimplied therefrom beyond the requirements of the prior art, because suchwords are used for description purposes herein and are intended to bebroadly construed. Moreover, the embodiments of the apparatusillustrated and described herein are by way of example, and the scope ofthe invention is not limited to the exact details of construction.

1. A method for constructing or rehabilitating a marsh or wetlandcomprising the steps of: inserting a propagatable material into liquidor slurry to form a mixture; spraying the liquid-propagatable materialmixture from a spray nozzle over a marsh or wetland area desired to berehabilitated; and channeling the propagatable material into acontainer; wherein the spraying step comprises placing the containerdownstream of a pump and upstream of the nozzle, and using the pump toeject the mixture; wherein the container is in fluid communication withan aperture in a hose extending between the pump and the nozzle; whereinthe propagatable material-inserting step comprises drawing thepropagatable material into the hose by means of a vacuum created at theaperture by fluid being directed from the pump to the nozzle; whereinthe propagatable material is inserted via a tube extending between thehose aperture and the container; and wherein the tube meets the hoseaperture at an angle that is adjustable for affecting a rate of thepropagatable material being drawn into the hose.
 2. The method recitedin claim 1, further comprising the step of adding to the liquid orslurry at least one of a fertilizer, a pH-adjusting composition, a seedstabilization and placement enhancer, and a slurry stabilizationenhancer.
 3. The method recited in claim 1, further comprising the stepsof extending a second hose from an upstream end of the pump to a body ofwater, and forming the liquid or slurry using water pumped from the bodyof water.
 4. The method recited in claim 1, further comprising the stepsof: dredging a marsh or wetland; using dredged material from thedredging step to form the liquid or slurry into which the propagatablematerial is inserted.
 5. A method for constructing or rehabilitating amarsh or wetland comprising the steps of: extending a first hose from anupstream end of a pump to a body of water; forming a liquid or slurryusing water pumped from the body of water; inserting a propagatablematerial into the liquid or slurry to form a mixture; spraying theliquid-propagatable material mixture from a spray nozzle over a marsh orwetland area desired to be rehabilitated; and channeling thepropagatable material into a container; wherein the spraying stepcomprises placing the container downstream of the pump and upstream ofthe nozzle, and using the pump to eject the mixture; wherein thecontainer is in fluid communication with an aperture in a second hoseextending between the pump and the nozzle; and wherein the propagatablematerial-inserting step comprises drawing the propagatable material intothe second hose by means of a vacuum created at the aperture by fluidbeing directed from the pump to the nozzle.
 6. The method recited inclaim 5, further comprising the step of adding to the liquid or slurryat least one of a fertilizer, a pH-adjusting composition, a seedstabilization and placement enhancer, and a slurry stabilizationenhancer.
 7. The method recited in claim 5, wherein the propagatablematerial is inserted via a tube extending between the hose aperture andthe container; and wherein the tube meets the hose aperture at an anglethat is adjustable for affecting a rate of the propagatable materialbeing drawn into the second hose.
 8. The method recited in claim 5,further comprising the steps of: dredging a marsh or wetland; usingdredged material from the dredging step to form the liquid or slurryinto which the propagatable material is inserted.